Electric heater



ELEGTRIG HEATER; I

Patented Mar. 17., I896.

(No Model.)

J. E. WILLIAMSON, (LE. COLLINS 8:; J. B. GRAHAM.

fizz/627M073. 5 414mm flflzbwases.

454mm. Q

UNITED STATES PATENT OFFICE.

JAMES E. XVILLIAMSON, CHARLES E. COLLINS, AND JOHN B. GRAHAM, OF ALLEGHENY, PENNSYLVANIA.

ELECTRIC HEATER.

SPECIFICATION forming part of Letters Patent No. 556,524, dated March 1'7, 1896.

Application filed February 9, 1894.

To all whom it may concern:

Be it known that we, J AMES E. WILLIAM- SON, CHARLES E. COLLINS, and JOHN B. GRA- HAM, citizens of the United States, residing at Allegheny, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Electric Heaters; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use the same, reference being had to the accompanying drawing, which forms a part of this specification.

Our invention belongs to that class of devices known as electric heaters, in which a quantity-current of electricity is caused to flow through a high resistance in the conductive path, thereby causing heat to be developed at the place of resistance. The specific object in this case is to produce a heater of form, design, and size adapted to be lowered into an oil-well and therein heated by a current generated at the surface, for the purpose of softening and liquefyin g the solid and semisolid products of petroleum occurring therein, which obstruct the flow, and thereby restoring the productive powers of the well.

Reference is made to the accompanying drawing, forming a part of this specification, showing a vertical sectional view of our improved heater and liquefier, in whioha is a perforated tube or cylinder adapted to be lowered into an oil-well, closed at both ends with caps 19 c, and provided with insulated conductor-wires, one of which terminates at e and the other at f, as shown. The conductor 6, which we make the positive conductor, is inclosed in the tube 72., made of insulating material, which terminates at its lower extremityin the fiarin g or bell mouth 2', which serves to prevent the immediate and rapid intermixture of the liquids entering the perforations in the upper part of the shell and those which have passed to the lower portion thereof.

The cylinder or shell is perforated through its wall to enable the fluids, consisting of impure oils, salts and hydrocarbonaceous material found therein to penetrate the same, and thus form a medium or path between the terminals, which, by its relatively-high resist- Serial No. 499,678. (No model.)

ance to the passage of the current, causes a high temperature to be generated within the shell, whereby the oil and fusible hydrocar- 5 j bons in the vicinity are softened and liquefied.

To aid the passage of the resistance-current, in case the fluids penetrating the perforated shell are insufficiently charged with salts,we place a charge of some salt, as sodium or ammonium chloride, in the bottom of the lower cap, as shown in the drawing in the dot-ted mass in the lower cap 0.

The cylinder is lowered into the well by a cord or line in the usual manner.

7e are aware that electric heaters onthe resistance principle are no novelty, and that modified forms of such heaters for use in oil-wells are old, and we do not claim such broadly; but

What we claim, and desire to secure by Let ters Patent, is

1. A11 electric heater for oil-wells, comprising a perforated cylinder or shell, closed at both ends with caps 19, 0, having a charge of salt in the lower cap, and provided with an insulated positive conductor-terminal, as e, inolosed in a bell-mouthed tube h, and an insulated negative conductor-terminal f,whereby when the interior space of the shell becomes filled through the perforations by the fluids of the well, carrying a salt in solution as specified, the passage of the current through the same from terminal to terminal develops heat along the path of high resistance thus afforded, and liquefies the semisolid hydrocarbons in the vicinity, substantially as speci- 2. The electric heater for oilwells, consisting of the-perforated shell a, screw-caps Z), c, 0 positive insulated conductor-terminal e, negative insulated cond uctor-terminal f, and tube h with bell-mouth "i, all substantially as shown and described.

In testimony that we claim the foregoing we hereunto affix our signatures this 5th day of February, A. D. 1894.

In presence of ALBERT J. WALKER, G. A. WILLIAMS. 

